Data &amp; Tools

Data &amp; Tools | Global Forest Watch Blog

deforestation

deforestation | Global Forest Watch Blog

forest change

forest change | Global Forest Watch Blog

Sarah Carter

Nancy Harris

Crystal Davis

Jan Hooijmans

<p>Today, we have more data about forests than ever before, but we still can’t seem to agree on where, when and why forests are changing around the world. Even two prominent global data sources appear to disagree, at least on the surface. “Deforestation continues to decline” was <a href="https://openknowledge.fao.org/server/api/core/bitstreams/2dee6e93-1988-4659-aa89-30dd20b43b15/content/FRA-2025/key-findings.html" target="_blank" rel="noreferrer noopener">a headline</a> of the <a href="https://www.fao.org/forest-resources-assessment/en/" target="_blank" rel="noreferrer noopener">2025 Global Forest Resources Assessment (FRA)</a> published by the United Nations Food and Agriculture Organization (FAO). At the same time, Global Forest Watch (GFW) <a href="https://gfr.wri.org/latest-analysis-deforestation-trends" target="_blank" rel="noreferrer noopener">reported that</a> “the tropics lost a record-shattering 6.7 million hectares of primary rainforest in 2024 … nearly double that of 2023.”</p>



<p>What gives? Unfortunately, the answer is not simple. Both GFW and FRA provide valuable information on the state of global forests, but they differ substantially in terms of purpose, scope and approach. By answering questions on how and why these two global data sources differ, we can begin to see them as complementary rather than contradictory. Ultimately, our knowledge of global forests remains incomplete, and we need all the information we can get.</p>



<div class="textboxright"><strong>WHAT ARE GLOBAL FOREST WATCH (GFW) AND THE GLOBAL FOREST RESOURCES ASSESSMENT (FRA)?</strong> <br><br>GFW is an independent online forest monitoring platform launched in 2014 by a consortium of partners led by World Resources Institute. GFW seeks to empower forest managers, law enforcement officers and other forest stakeholders with free access to timely and high-resolution data about the current status of forests and recent forest change. GFW uses satellite technology to monitor tree cover loss worldwide with weekly and annual updates, as well as to provide longer term tree cover gain and net change data. Gain, net change and annual loss data are GFW’s core data sets and are provided by the University of Maryland. Other data sets on GFW provide useful contextual information related to forests and forest change.<br><br>

The FRA, which the FAO has published at 5- to 10-year intervals since 1946, seeks to provide a consistent and comprehensive approach to describing the world’s forests and how they are changing. Countries provide reports to FRA based on data from National Forest Inventories, satellite data and extrapolation based on past data. The FAO combines the data submitted by countries into global reports and fills in any gaps where data is not available from the countries. The most recent edition of the FRA in 2025 included national-level statistics on around 50 broad ecological and socio-economic variables reported by 236 countries and territories. </div>



<h2 class="wp-block-heading">What is considered a “forest”?</h2>



<p>GFW and FRA both talk about “forests,” but what are they actually measuring and monitoring? There are nearly&nbsp;<a href="https://www.nrs.fs.usda.gov/pubs/gtr/gtr_wo077/gtr_wo077_011.pdf" target="_blank" rel="noreferrer noopener">800 definitions</a>&nbsp;of “forest” in use, which only adds to the confusion.</p>



<p>Every five years, FRA publishes forest area globally and per country. These area measurements are based on a <a href="https://openknowledge.fao.org/server/api/core/bitstreams/a6e225da-4a31-4e06-818d-ca3aeadfd635/content" target="_blank" rel="noreferrer noopener">standardized&nbsp;definition</a>&nbsp;of “forest” adopted by the FAO in 2000, which takes into account biophysical and land use criteria. The biophysical criterion establishes minimum thresholds for the height, canopy cover and extent of trees. The land use criterion requires that land be officially or legally designated for a “forest use,” such as conservation or harvest. Land that contains trees but is designated for agricultural or urban uses — for example, an oil palm plantation, shade grown cocoa (agroforestry) or a city park — would not be considered a forest. At the same time, land that is temporarily devoid of trees — for example, recently logged or burned areas — would still be classified as forest if the official land use stipulates that trees will be allowed to regenerate in the future.</p>



<p>GFW provides data on “tree cover,” which is derived from satellite data and therefore cannot discern intended land use. Thus, GFW’s monitoring systems rely entirely on biophysical criteria — related to height, canopy cover and extent of trees. GFW does not adopt a specific definition of forest, but rather monitors all forms of tree cover including natural forests and tree plantations. Using GFW’s interactive online platform, users can filter this data based on their preferred definition of forest. Users can select by canopy cover percent, as well as tree height. Users can also view and derive statistics using other data sets that give additional context on the land use, such as <a href="https://gfw.global/3jyrlta">primary forests</a>, <a href="http://gfw.global/4fQfl03">natural forests</a> and <a href="https://gfw.global/2Qbv7fM">planted trees</a>.</p>


<div class="wp-block-image">
<figure class="aligncenter size-large"><img decoding="async" loading="lazy" width="2048" height="1867" src="https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_What-is-considered-a-forest-1-2048x1867.png" alt="What is considered a "Forest" by GFW and FRA?" class="wp-image-16209" srcset="https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_What-is-considered-a-forest-1-2048x1867.png 2048w, https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_What-is-considered-a-forest-1-1024x934.png 1024w, https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_What-is-considered-a-forest-1-768x700.png 768w, https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_What-is-considered-a-forest-1-1536x1401.png 1536w" sizes="(max-width: 2048px) 100vw, 2048px" /></figure></div>


<h2 class="wp-block-heading">How is “forest change” reported?</h2>



<p>Both FRA and GFW aggregate monitoring data into global statistics about forest change. Like the different ways they measure forests, GFW and FRA apply different lenses to monitor <em>changes to</em> forests, which subsequently influence how both forest expansion and deforestation are reported. GFW reports annual gross loss of tree cover, as well as gross gain for four 5-year periods and net change for a 20-year period. FRA reports on deforestation, net change and forest expansion as separate statistics, though many countries only report forest area, from which net change can be derived.</p>



<h3 class="wp-block-heading">Deforestation and tree cover loss</h3>



<p>Using its land use criterion, the FAO’s definition of deforestation requires permanent land use change to occur. Losses of tree cover considered to be temporary (e.g., forests that have been clear cut but will be left to regrow) are not counted as deforestation.</p>



<p>Conversely, GFW detects and reports all instances of tree cover loss, regardless of whether the loss will be temporary or permanent (e.g., clear cut harvest followed by agriculture). As with forests, GFW does not seek to define deforestation but rather allows users to filter tree cover loss data based on their own preferred definition.</p>



<p>Though GFW data includes all forms of tree cover loss, data on certain drivers of loss is available on GFW, such as <a href="https://gfw.global/3eO7ZjW">tree cover loss due to fires</a> and <a href="https://gfw.global/39qbPdC">tree cover loss by dominant driver,</a> the latter of which can be used to better align with the definition of deforestation used by FRA. GFW uses the tree cover loss by dominant driver data to create a “<a href="https://research.wri.org/gfr/data-methods#forestchange1" target="_blank" rel="noreferrer noopener">deforestation proxy</a>” consisting of tree cover loss due to shifting agricultural expansion into primary forests, commodity-driven deforestation and urbanization. GFW users can also filter the tree cover loss data by primary forest and natural forest to view and download statistics for just these areas.</p>



<p>FRA deforestation data is available for the 5- or 10-year reporting periods, while GFW tree cover loss data is available annually.</p>



<h3 class="wp-block-heading">Forest expansion, tree cover gain and reforestation</h3>



<p>As with the deforestation data, information on forest expansion is available for the FRA reporting periods of 5 or 10 years. In FRA, forest expansion can be due to afforestation or a natural expansion of forest area.</p>



<p>GFW data on tree cover gain is available for 5-year time periods between 2000-2020. Like with the tree cover data, GFW gain data includes regrowth in plantations following harvesting, which would not be included in forest expansion according to FRA.</p>



<p>FRA also provides reforestation data, which does not influence forest area or their net change figure. FRA defines reforestation as the planting of trees in areas already considered as forests by FAO’s land use criterion.</p>



<h3 class="wp-block-heading">Forest area and tree cover net change</h3>



<p>FRA and GFW report net change in forest and tree cover extent respectively. GFW net change data currently only compares 2000 to 2020. FRA data is available for their 5- or 10-year reporting periods.</p>


<div class="wp-block-image">
<figure class="aligncenter size-large"><img decoding="async" loading="lazy" width="1583" height="2048" src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_Forest_types_table-1-1583x2048.png" alt="" class="wp-image-19767" srcset="https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_Forest_types_table-1-1583x2048.png 1583w, https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_Forest_types_table-1-791x1024.png 791w, https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_Forest_types_table-1-768x994.png 768w, https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_Forest_types_table-1-1187x1536.png 1187w" sizes="(max-width: 1583px) 100vw, 1583px" /></figure></div>


<h2 class="wp-block-heading">Where is the data from?</h2>



<p>FRA compiles official government statistics on forest-related information. This data is self-reported by countries and can come from different sources using a variety of methods, including national forest inventories (NFIs), academic studies, government registries or district forest offices. Remote sensing (RS) is becoming more frequently used as an input into some nationally reported data. Although FAO provides guidelines on what and how to report, in reality, many countries employ their own definitions and methods.</p>



<p>GFW features data that is based on satellite data, providing an independent, transparent and globally consistent record of Earth’s land surface and how it is changing. This record enables consistent comparisons across countries and over time.</p>


<div class="wp-block-image">
<figure class="aligncenter size-large"><img decoding="async" loading="lazy" width="2048" height="1612" src="https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_Where-is-data-from-1-2048x1612.png" alt="Where is the data from for GFW and FRA?" class="wp-image-16211" srcset="https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_Where-is-data-from-1-2048x1612.png 2048w, https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_Where-is-data-from-1-1024x806.png 1024w, https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_Where-is-data-from-1-768x605.png 768w, https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_Where-is-data-from-1-1536x1209.png 1536w" sizes="(max-width: 2048px) 100vw, 2048px" /></figure></div>


<h2 class="wp-block-heading">When is the data collected and reported?</h2>



<p>FRA reports are released every 5 years based on countries’ reported information. Some countries update their forest information systems frequently, while others update them only every 10-20 years, meaning some FRA reports are based on older data. When country reports are unavailable, the FAO fills in gaps using available literature and expert estimates. <a href="https://iopscience.iop.org/article/10.1088/1748-9326/abd81b/meta" target="_blank" rel="noreferrer noopener">A study examining the 2020 FRA data sources</a> showed the most recent years in which RS and NFI data were collected and found that although many countries use data that are only a few years old, there are a number of countries using data over 30 years old.</p>



<p>GFW’s tree cover loss data set is updated each year with the previous year’s data. GFW’s net change and gain data covers the 20-year period from 2000 to 2020, with plans underway for more frequent updates.</p>


<div class="wp-block-image">
<figure class="aligncenter size-large"><img decoding="async" loading="lazy" width="2048" height="1188" src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_GFW_vs_FAO_graphics_When-is-data-reported-2048x1188.png" alt="" class="wp-image-19766" srcset="https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_GFW_vs_FAO_graphics_When-is-data-reported-2048x1188.png 2048w, https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_GFW_vs_FAO_graphics_When-is-data-reported-1024x594.png 1024w, https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_GFW_vs_FAO_graphics_When-is-data-reported-768x445.png 768w, https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_GFW_vs_FAO_graphics_When-is-data-reported-1536x891.png 1536w" sizes="(max-width: 2048px) 100vw, 2048px" /></figure></div>


<h2 class="wp-block-heading">What is the unit of analysis?</h2>



<p>FRA collects statistics at the national scale, which are aggregated to provide insights about forest change dynamics regionally and globally.</p>



<p>Satellite-based data on GFW records changes in forest area by dividing Earth’s land surface into pixels. These pixels — which for most data on forest area and change are 30 m by 30 m in size — can then be aggregated to show changes over larger areas of interest. This modular format means that in addition to understanding forest dynamics at global, regional and national scales (as with the FRA), users can also monitor changes within custom areas of interest, such as a specific national park in their country, a provincial district, an Indigenous territory or even their own backyards.</p>


<div class="wp-block-image">
<figure class="aligncenter size-large"><img decoding="async" loading="lazy" width="1275" height="1223" src="https://content.globalforestwatch.org/wp-content/uploads/2023/07/GFW_vs_FAO_graphics_final-05.png" alt="What is the unit of analysis for GFW vs FRA?" class="wp-image-16213" srcset="https://content.globalforestwatch.org/wp-content/uploads/2023/07/GFW_vs_FAO_graphics_final-05.png 1275w, https://content.globalforestwatch.org/wp-content/uploads/2023/07/GFW_vs_FAO_graphics_final-05-1024x982.png 1024w, https://content.globalforestwatch.org/wp-content/uploads/2023/07/GFW_vs_FAO_graphics_final-05-768x737.png 768w" sizes="(max-width: 1275px) 100vw, 1275px" /></figure></div>


<h2 class="wp-block-heading">What does it all mean?</h2>



<p>How one defines forest, deforestation, reforestation and forest expansion is at the heart of the confusion and controversies surrounding these two data sources. Critics of FRA point out that country-reported data may be outdated, inconsistent, incomplete or based on non-transparent methods. In addition, FAO’s net forest change statistic (which is the only forest change variable presented for many countries) provides an overly optimistic view of global forest trends since by their definition, the loss of natural forests — rich in biodiversity and carbon — can be offset by expansion of tree plantation monocultures. The same applies for GFW’s net change information when viewed without the contextual data sets.</p>



<p>Meanwhile, critics of GFW claim that satellite-based monitoring has fundamental limitations on what can be observed from satellites, and that tree cover loss creates an overly pessimistic view since these data lump together permanent and temporary loss of tree cover within natural forests and tree plantations. In the case of FRA, temporary loss is not included in deforestation information.</p>



<p>Ultimately, neither GFW nor FRA is perfect or complete, but they both have important, and complementary, applications.</p>



<h2 class="wp-block-heading">When might I use GFW or FRA?</h2>



<p>Bottom-up approaches like FRA benefit from locally appropriate methodologies, customization of data and use of country definitions — although many countries follow the FAO’s standard definitions. FRA is more comprehensive in scope, ranging from biophysical to socio-economic and legislative variables. FRA’s data will be relevant for those that have a broad interest in the state of forests in a country and how they are being managed.</p>



<p>However, FRA’s data is only reported on a national level and cannot be used for assessing regional differences within countries. GFW’s spatially precise updates on tree cover loss allow users to track where changes in tree cover are happening on a sub-national level. GFW also offers more consistency in methods and definitions across geographies for making comparisons across countries.</p>



<p>GFW currently provides more frequent tree cover loss information (annually, and in near-real-time) than FRA does on deforestation, while FRA currently provides more up-to-date information on forest expansion than GFW does on tree cover gain — though GFW will eventually provide annual tree cover gain data. FRA’s figures also reflect tree planting initiatives that are too recent to be picked up by satellite data, although not all of these projects are successful.</p>



<p>In the end, the differences between GFW and FRA reveal strengths and shortcomings of both sources that make them appropriate for different applications, meaning that both are useful to understand what is happening with the world’s forests.</p>



<p></p>



<p><em>This blog was originally published in 2023. It was updated in October 2025 to reflect the latest updates to GFW and the FRA.</em> <em>Rachael Petersen and Octavia Payne contributed to a previous version of this blog.</em></p>



<style type="text/css"></style>



<p><style type="text/css"></style></p>

Global Forest Watch and the Forest Resources Assessment, Explained in 5 Graphics

<p>Today, we have more data about forests than ever before, but we still can’t seem to agree on where, when and why forests are changing around the world. Even two prominent global data sources appear to disagree, at least on the surface. “Deforestation continues to decline” was <a href="https://openknowledge.fao.org/server/api/core/bitstreams/2dee6e93-1988-4659-aa89-30dd20b43b15/content/FRA-2025/key-findings.html" target="_blank" rel="noreferrer noopener">a headline</a> of the <a href="https://www.fao.org/forest-resources-assessment/en/" target="_blank" rel="noreferrer noopener">2025 Global Forest Resources Assessment (FRA)</a> published by the United Nations Food and Agriculture Organization (FAO). At the same time, Global Forest Watch (GFW) <a href="https://gfr.wri.org/latest-analysis-deforestation-trends" target="_blank" rel="noreferrer noopener">reported that</a> “the tropics lost a record-shattering 6.7 million hectares of primary rainforest in 2024 ... nearly double that of 2023.”</p>



<p>What gives? Unfortunately, the answer is not simple. Both GFW and FRA provide valuable information on the state of global forests, but they differ substantially in terms of purpose, scope and approach. By answering questions on how and why these two global data sources differ, we can begin to see them as complementary rather than contradictory. Ultimately, our knowledge of global forests remains incomplete, and we need all the information we can get.</p>



<div class="textboxright"><strong>WHAT ARE GLOBAL FOREST WATCH (GFW) AND THE GLOBAL FOREST RESOURCES ASSESSMENT (FRA)?</strong> <br><br>GFW is an independent online forest monitoring platform launched in 2014 by a consortium of partners led by World Resources Institute. GFW seeks to empower forest managers, law enforcement officers and other forest stakeholders with free access to timely and high-resolution data about the current status of forests and recent forest change. GFW uses satellite technology to monitor tree cover loss worldwide with weekly and annual updates, as well as to provide longer term tree cover gain and net change data. Gain, net change and annual loss data are GFW’s core data sets and are provided by the University of Maryland. Other data sets on GFW provide useful contextual information related to forests and forest change.<br><br>

The FRA, which the FAO has published at 5- to 10-year intervals since 1946, seeks to provide a consistent and comprehensive approach to describing the world’s forests and how they are changing. Countries provide reports to FRA based on data from National Forest Inventories, satellite data and extrapolation based on past data. The FAO combines the data submitted by countries into global reports and fills in any gaps where data is not available from the countries. The most recent edition of the FRA in 2025 included national-level statistics on around 50 broad ecological and socio-economic variables reported by 236 countries and territories. </div>



<h2 class="wp-block-heading">What is considered a “forest”?</h2>



<p>GFW and FRA both talk about “forests,” but what are they actually measuring and monitoring? There are nearly&nbsp;<a href="https://www.nrs.fs.usda.gov/pubs/gtr/gtr_wo077/gtr_wo077_011.pdf" target="_blank" rel="noreferrer noopener">800 definitions</a>&nbsp;of “forest” in use, which only adds to the confusion.</p>



<p>Every five years, FRA publishes forest area globally and per country. These area measurements are based on a <a href="https://openknowledge.fao.org/server/api/core/bitstreams/a6e225da-4a31-4e06-818d-ca3aeadfd635/content" target="_blank" rel="noreferrer noopener">standardized&nbsp;definition</a>&nbsp;of “forest” adopted by the FAO in 2000, which takes into account biophysical and land use criteria. The biophysical criterion establishes minimum thresholds for the height, canopy cover and extent of trees. The land use criterion requires that land be officially or legally designated for a “forest use,” such as conservation or harvest. Land that contains trees but is designated for agricultural or urban uses — for example, an oil palm plantation, shade grown cocoa (agroforestry) or a city park — would not be considered a forest. At the same time, land that is temporarily devoid of trees — for example, recently logged or burned areas — would still be classified as forest if the official land use stipulates that trees will be allowed to regenerate in the future.</p>



<p>GFW provides data on “tree cover,” which is derived from satellite data and therefore cannot discern intended land use. Thus, GFW’s monitoring systems rely entirely on biophysical criteria — related to height, canopy cover and extent of trees. GFW does not adopt a specific definition of forest, but rather monitors all forms of tree cover including natural forests and tree plantations. Using GFW’s interactive online platform, users can filter this data based on their preferred definition of forest. Users can select by canopy cover percent, as well as tree height. Users can also view and derive statistics using other data sets that give additional context on the land use, such as <a href="https://gfw.global/3jyrlta">primary forests</a>, <a href="http://gfw.global/4fQfl03">natural forests</a> and <a href="https://gfw.global/2Qbv7fM">planted trees</a>.</p>



<figure class="wp-block-image aligncenter size-large"><img src="https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_What-is-considered-a-forest-1-2048x1867.png" alt="What is considered a &quot;Forest&quot; by GFW and FRA?" class="wp-image-16209"/></figure>



<h2 class="wp-block-heading">How is “forest change” reported?</h2>



<p>Both FRA and GFW aggregate monitoring data into global statistics about forest change. Like the different ways they measure forests, GFW and FRA apply different lenses to monitor <em>changes to</em> forests, which subsequently influence how both forest expansion and deforestation are reported. GFW reports annual gross loss of tree cover, as well as gross gain for four 5-year periods and net change for a 20-year period. FRA reports on deforestation, net change and forest expansion as separate statistics, though many countries only report forest area, from which net change can be derived.</p>



<h3 class="wp-block-heading">Deforestation and tree cover loss</h3>



<p>Using its land use criterion, the FAO’s definition of deforestation requires permanent land use change to occur. Losses of tree cover considered to be temporary (e.g., forests that have been clear cut but will be left to regrow) are not counted as deforestation.</p>



<p>Conversely, GFW detects and reports all instances of tree cover loss, regardless of whether the loss will be temporary or permanent (e.g., clear cut harvest followed by agriculture). As with forests, GFW does not seek to define deforestation but rather allows users to filter tree cover loss data based on their own preferred definition.</p>



<p>Though GFW data includes all forms of tree cover loss, data on certain drivers of loss is available on GFW, such as <a href="https://gfw.global/3eO7ZjW">tree cover loss due to fires</a> and <a href="https://gfw.global/39qbPdC">tree cover loss by dominant driver,</a> the latter of which can be used to better align with the definition of deforestation used by FRA. GFW uses the tree cover loss by dominant driver data to create a “<a href="https://research.wri.org/gfr/data-methods#forestchange1" target="_blank" rel="noreferrer noopener">deforestation proxy</a>” consisting of tree cover loss due to shifting agricultural expansion into primary forests, commodity-driven deforestation and urbanization. GFW users can also filter the tree cover loss data by primary forest and natural forest to view and download statistics for just these areas.</p>



<p>FRA deforestation data is available for the 5- or 10-year reporting periods, while GFW tree cover loss data is available annually.</p>



<h3 class="wp-block-heading">Forest expansion, tree cover gain and reforestation</h3>



<p>As with the deforestation data, information on forest expansion is available for the FRA reporting periods of 5 or 10 years. In FRA, forest expansion can be due to afforestation or a natural expansion of forest area.</p>



<p>GFW data on tree cover gain is available for 5-year time periods between 2000-2020. Like with the tree cover data, GFW gain data includes regrowth in plantations following harvesting, which would not be included in forest expansion according to FRA.</p>



<p>FRA also provides reforestation data, which does not influence forest area or their net change figure. FRA defines reforestation as the planting of trees in areas already considered as forests by FAO’s land use criterion.</p>



<h3 class="wp-block-heading">Forest area and tree cover net change</h3>



<p>FRA and GFW report net change in forest and tree cover extent respectively. GFW net change data currently only compares 2000 to 2020. FRA data is available for their 5- or 10-year reporting periods.</p>



<figure class="wp-block-image aligncenter size-large"><img src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_Forest_types_table-1-1583x2048.png" alt="" class="wp-image-19767"/></figure>



<h2 class="wp-block-heading">Where is the data from?</h2>



<p>FRA compiles official government statistics on forest-related information. This data is self-reported by countries and can come from different sources using a variety of methods, including national forest inventories (NFIs), academic studies, government registries or district forest offices. Remote sensing (RS) is becoming more frequently used as an input into some nationally reported data. Although FAO provides guidelines on what and how to report, in reality, many countries employ their own definitions and methods.</p>



<p>GFW features data that is based on satellite data, providing an independent, transparent and globally consistent record of Earth’s land surface and how it is changing. This record enables consistent comparisons across countries and over time.</p>



<figure class="wp-block-image aligncenter size-large"><img src="https://content.globalforestwatch.org/wp-content/uploads/2023/07/23_GFW_vs_FAO_graphics_Where-is-data-from-1-2048x1612.png" alt="Where is the data from for GFW and FRA?" class="wp-image-16211"/></figure>



<h2 class="wp-block-heading">When is the data collected and reported?</h2>



<p>FRA reports are released every 5 years based on countries’ reported information. Some countries update their forest information systems frequently, while others update them only every 10-20 years, meaning some FRA reports are based on older data. When country reports are unavailable, the FAO fills in gaps using available literature and expert estimates. <a href="https://iopscience.iop.org/article/10.1088/1748-9326/abd81b/meta" target="_blank" rel="noreferrer noopener">A study examining the 2020 FRA data sources</a> showed the most recent years in which RS and NFI data were collected and found that although many countries use data that are only a few years old, there are a number of countries using data over 30 years old.</p>



<p>GFW’s tree cover loss data set is updated each year with the previous year’s data. GFW’s net change and gain data covers the 20-year period from 2000 to 2020, with plans underway for more frequent updates.</p>



<figure class="wp-block-image aligncenter size-large"><img src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/25_GFW_vs_FAO_graphics_When-is-data-reported-2048x1188.png" alt="" class="wp-image-19766"/></figure>



<h2 class="wp-block-heading">What is the unit of analysis?</h2>



<p>FRA collects statistics at the national scale, which are aggregated to provide insights about forest change dynamics regionally and globally.</p>



<p>Satellite-based data on GFW records changes in forest area by dividing Earth’s land surface into pixels. These pixels — which for most data on forest area and change are 30 m by 30 m in size — can then be aggregated to show changes over larger areas of interest. This modular format means that in addition to understanding forest dynamics at global, regional and national scales (as with the FRA), users can also monitor changes within custom areas of interest, such as a specific national park in their country, a provincial district, an Indigenous territory or even their own backyards.</p>



<figure class="wp-block-image aligncenter size-large"><img src="https://content.globalforestwatch.org/wp-content/uploads/2023/07/GFW_vs_FAO_graphics_final-05.png" alt="What is the unit of analysis for GFW vs FRA?" class="wp-image-16213"/></figure>



<h2 class="wp-block-heading">What does it all mean?</h2>



<p>How one defines forest, deforestation, reforestation and forest expansion is at the heart of the confusion and controversies surrounding these two data sources. Critics of FRA point out that country-reported data may be outdated, inconsistent, incomplete or based on non-transparent methods. In addition, FAO’s net forest change statistic (which is the only forest change variable presented for many countries) provides an overly optimistic view of global forest trends since by their definition, the loss of natural forests — rich in biodiversity and carbon — can be offset by expansion of tree plantation monocultures. The same applies for GFW’s net change information when viewed without the contextual data sets.</p>



<p>Meanwhile, critics of GFW claim that satellite-based monitoring has fundamental limitations on what can be observed from satellites, and that tree cover loss creates an overly pessimistic view since these data lump together permanent and temporary loss of tree cover within natural forests and tree plantations. In the case of FRA, temporary loss is not included in deforestation information.</p>



<p>Ultimately, neither GFW nor FRA is perfect or complete, but they both have important, and complementary, applications.</p>



<h2 class="wp-block-heading">When might I use GFW or FRA?</h2>



<p>Bottom-up approaches like FRA benefit from locally appropriate methodologies, customization of data and use of country definitions — although many countries follow the FAO’s standard definitions. FRA is more comprehensive in scope, ranging from biophysical to socio-economic and legislative variables. FRA's data will be relevant for those that have a broad interest in the state of forests in a country and how they are being managed.</p>



<p>However, FRA's data is only reported on a national level and cannot be used for assessing regional differences within countries. GFW’s spatially precise updates on tree cover loss allow users to track where changes in tree cover are happening on a sub-national level. GFW also offers more consistency in methods and definitions across geographies for making comparisons across countries.</p>



<p>GFW currently provides more frequent tree cover loss information (annually, and in near-real-time) than FRA does on deforestation, while FRA currently provides more up-to-date information on forest expansion than GFW does on tree cover gain — though GFW will eventually provide annual tree cover gain data. FRA’s figures also reflect tree planting initiatives that are too recent to be picked up by satellite data, although not all of these projects are successful.</p>



<p>In the end, the differences between GFW and FRA reveal strengths and shortcomings of both sources that make them appropriate for different applications, meaning that both are useful to understand what is happening with the world’s forests.</p>



<p></p>



<p><em>This blog was originally published in 2023. It was updated in October 2025 to reflect the latest updates to GFW and the FRA.</em> <em>Rachael Petersen and Octavia Payne contributed to a previous version of this blog.</em></p>



<style type="text/css"></style>



<p><style type="text/css"></style></p>

Both GFW and FRA provide valuable information on the state of forests, and they both have important, and complementary, applications.

Global Forest Watch and Forest Resources Assessment | GFW Blog

Comment

Global Forest Watch Content

https://content.globalforestwatch.org/wp-content/uploads/2018/06/gfwGlobal.png

https://secure.gravatar.com/avatar/bf3dd86ffe8c109dcc6ad6d415f8ad0b?s=96&d=mm&r=g

James Anderson

Forest Insights

Forest Insights | Global Forest Watch Blog

Biodiversity

Biodiversity | Global Forest Watch Blog

Lucienne Wilmé

Ollier Andrianambinina

Kevin Faragher

From Global to Local: Tailoring Forest Monitoring in Madagascar with Global Forest Watch Data

<p>Understanding deforestation in Madagascar is incredibly important for protecting the country’s extraordinary biodiversity. Over 80% of the species are endemic, found nowhere else on Earth. This biodiversity underpins the ecosystem services that sustain daily life across the island — from clean water and fertile soils to climate regulation and cultural identity. Accurate, independent monitoring of Madagascar’s natural forests helps to prioritize conservation actions, safeguard these services and ensure that all people living in Madagascar continue to benefit from the natural capital essential to their livelihoods, climate adaptation and sustainable future.</p>



<figure class="wp-block-image size-large"><img src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/Picture1-2048x1366.jpg" alt="Diademed sifaka (Propithecus diadema), Mantadia National Park. Credit: Catherine Sauvi" class="wp-image-19591"/><figcaption class="wp-element-caption"><em>Diademed sifaka (</em>Propithecus diadema<em>), Mantadia National Park. Credit: Catherine Sauvin</em></figcaption></figure>



<p>But until recently, up-to-date information on deforestation in Madagascar was limited. Global Forest Watch (GFW) offers transparent tools designed to monitor forests consistently everywhere. GFW’s global tree cover loss data and tree canopy density maps measure annual changes and extent and are incredibly valuable for providing frequently updated, comparable and consistent estimates across the world.</p>



<p>However, they do not match each local definition and context that may be crucial for planning and conservation. For example, GFW’s tree cover loss data shows loss of all tree cover, including tree loss in agriculture areas, tree plantations and other non-natural forests. As such, this data <a href="https://doi.org/10.1016/j.biocon.2018.04.008" target="_blank" rel="noreferrer noopener">must be filtered to identify deforestation</a>.</p>



<p>In 2024, the research team from WRI Madagascar developed an approach to bridge the gap between global tree cover loss data and deforestation within Madagascar’s natural forests to develop an actionable deforestation estimate for national planning, reporting and conservation decision-making.</p>



<h2 class="wp-block-heading"><strong>Adapting GFW data for Madagascar</strong><a href="https://doi.org/10.1016/j.biocon.2018.04.008"></a></h2>



<p>To assess deforestation in Madagascar, we used two key global data sets: <a href="https://gfw.global/4c7eHcL">tree canopy density (TCD)</a>, which shows the percentage of canopy cover in each 30-meter pixel in the year 2000, and <a href="https://gfw.global/3BfwQWz">annual tree cover loss</a>, which tracks where those pixels lost canopy cover in subsequent years.</p>



<p>The goal was to develop a methodology for tailoring global tree cover loss data sets to detect loss within Madagascar’s natural forests. However, the TCD and tree cover loss data include areas of tree cover that do not meet Madagascar’s ecological definitions of forest, like tree plantations. This is particularly important in Madagascar, where vast areas are dominated by <em>Ravenala</em> species, or traveler’s palms — not true palms but relatives of bananas — which are endemic to Madagascar but often form stands limited to one species after clearing, and are typically poor in biodiversity. These areas are frequently classified as tree cover in satellite data, though they lack the structure, species richness and ecological function of natural forests.</p>



<figure class="wp-block-image size-full"><img src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/Travelers-palms.-Credit-Dicklyon.jpg" alt="Traveler’s palms. Credit: Dicklyon" class="wp-image-19594"/><figcaption class="wp-element-caption"><em>Traveler’s palms. Credit: Dicklyon</em></figcaption></figure>



<p>As such, we focused our analysis on natural forests, with natural forest loss as a proxy for deforestation. We overlaid the TCD and tree cover loss data onto a <a href="https://doi.org/10.1016/j.biocon.2018.04.008" target="_blank" rel="noreferrer noopener">nationally validated</a> natural forest map for Madagascar for the year 2000 to provide an actionable deforestation estimate. This may slightly overestimate deforestation (defined as permanent change from forest to other land uses) since natural forest loss can include temporary disturbances such as wildfire or vegetation clearing for shifting cultivation. However, ecological recovery in these forests can be extremely slow, meaning natural forest loss estimates provide a meaningful proxy for the purposes of national planning, reporting and conservation decision-making.  </p>



<h2 class="wp-block-heading"><strong>Identifying loss in Madagascar’s natural forests</strong></h2>



<p>GFW allows users to select their own TCD threshold to map their forest area; however, for global consistency, GFW typically uses a standard TCD threshold — generally 30% tree cover density — which can exclude many naturally more open forest types. For example, in Madagascar, applying TCD &gt;30% misses large areas of dry and spiny forests. As a result, no loss is detected there simply because those areas are not counted as forest to begin with.</p>



<figure class="wp-block-image size-full"><img src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/Picture3.jpg" alt="Baobab tree (Adansonia rubrostipa) in the southern spiny forest, Tsimanampesotse National Pa" class="wp-image-19595"/><figcaption class="wp-element-caption"><em>Baobab tree </em>(Adansonia rubrostipa)<em> in the southern spiny forest, Tsimanampesotse National Park</em></figcaption></figure>



<p>Therefore, instead of assigning a single threshold per forest type, our approach applies <a href="https://doi.org/10.3390/land14040698" target="_blank" rel="noreferrer noopener">locally adapted TCD thresholds</a> to each pixel in the 2000 natural forest map of Madagascar so that deforestation can be tracked more accurately across all forest types. For each non-contiguous forest parcel based on its known extent in 2000, we identified the <a href="https://doi.org/10.3390/land14040698" target="_blank" rel="noreferrer noopener">most appropriate TCD threshold</a>. <a href="https://doi.org/10.1088/2515-7620/ace87f" target="_blank" rel="noreferrer noopener">Learn more here</a> about how these thresholds were calibrated. For <a href="https://doi.org/10.3390/land14040698" target="_blank" rel="noreferrer noopener">large forest blocks</a>, we split them into smaller, ecologically meaningful units to improve TCD accuracy. This subdivision was done as objectively as possible, using both the <a href="https://kew.iro.bl.uk/concern/books/614e90f8-34f3-468f-956c-8574f21a1e4d" target="_blank" rel="noreferrer noopener">Vegetation Atlas</a> (validated by the government) and topographic relief, since elevation and terrain strongly influence forest structure.</p>



<p>Once these nationally adapted TCD thresholds were assigned at a pixel level across all natural forests, we combined them with GFW’s annual tree cover loss data to assess deforestation in every forest parcel, across all forest types and all regions of Madagascar. This produced an ecologically grounded monitoring system capable of informing both national reporting and local planning, and one that can be adapted and replicated in other countries. &nbsp;</p>



<figure class="wp-block-image size-full"><img src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/TCD-map-EN.png" alt="" class="wp-image-19596"/></figure>



<p><em>Natural forest cover in Madagascar (year 2000) and its relationship to tree canopy density (TCD) thresholds. A: Independent baseline natural forest cover for 2000; B: Same forest cover map as A with pixel-level TCD values assigned; C: Tree cover extent after applying the optimal TCD threshold producing an area estimate closest to the true natural forest extent; D–F: Tree cover area when applying standard TCD thresholds, with total area estimates showing either overestimation or underestimation of tree cover. These maps also reveal major geographic misalignment— particularly in dry forest regions — highlighting the need for locally adapted thresholds</em>.</p>



<p>This map now serves as a robust baseline for monitoring change. By overlaying annual tree cover loss on top of these forest pixels, we can consistently estimate deforestation across the country for any year — whether nationally, by region, or within protected areas.</p>



<p>This approach gives Madagascar a more ecologically meaningful measure of forest loss than the conventional global method. In 2024, using our method, we estimated a national deforestation total of 117,600 hectares — nearly half the figure produced by the global 30% threshold approach. This information supports national reporting obligations, aligns with local forest definitions and strengthens conservation efforts targeting habitats critical to Madagascar’s unique biodiversity.</p>



<figure class="wp-block-image size-full"><img src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/Picture5.jpg" alt="Madagascar ibis (Lophotibis cristata), Mantadia National Park. Credit: Catherine Sauvin" class="wp-image-19597"/><figcaption class="wp-element-caption"><em>Madagascar ibis (</em>Lophotibis cristata<em>), Mantadia National Park. Credit: Catherine Sauvin</em></figcaption></figure>



<h2 class="wp-block-heading"><strong>How Madagascar’s deforestation estimates support decision-making</strong></h2>



<p>Our approach makes use of the GFW’s freely available independent global data while adapting it to local realities.</p>



<p>Locally tailored information means that it is more suitable for use in regions, districts and communes — administrative units with their own budgets, plans and policies. In Madagascar, stakeholders responsible for these tasks can include regional and district heads appointed by the central government, and mayors who are elected at the commune levels, as well as VOIs (<em>Vondron’Olona Ifotony</em>) — local associations of villages and hamlets formally recognized as stewards of natural resources — and in the case of privately owned land, corporate entities and private individuals.</p>



<p>For all stakeholders, our monitoring approach provides relevant information. Across all landscapes and land statuses, one of the key use cases is for conservation of protected areas (e.g., Madagascar National Parks), VOIs and other zones critical for threatened endemic biodiversity. Tracking deforestation within both Protected Area boundaries and VOI-managed zones can offer powerful insights to enhance transparency, accountability and targeted support for locally grounded conservation efforts.</p>



<p>Because thresholds are locally adapted, this approach helps build trust in the results by aligning with what people see on the ground. It reduces the risk of misinterpreting features such as <em>Ravenala </em>stands, heavily degraded forests or other non-forest areas as “forest,” which can otherwise misdirect conservation or restoration resources. By clearly distinguishing natural forests of high ecological value, the data avoids misunderstandings and supports more accountable, effective decision-making. It allows stakeholders to identify priority areas and plan targeted interventions, including for restoration efforts, by helping define where forest losses have occurred and where restoration efforts should be focused and monitored.</p>



<figure class="wp-block-image size-large"><img src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/Picture6-2048x1366.jpg" alt="Patrols in a western dry forest." class="wp-image-19600"/><figcaption class="wp-element-caption"><em>Patrols in a western dry forest.</em></figcaption></figure>



<p>Additionally, Madagascar can now better prioritize conservation of habitats critical for endemic species, integrate biodiversity goals into development planning and ensure long-term sustainability of its forest resources.</p>



<figure class="wp-block-image size-large"><img src="https://content.globalforestwatch.org/wp-content/uploads/2025/10/Picture4-2048x1366.jpg" alt="Black-and-white ruffed lemur (Varecia v. variegata), Mantadia National Park. Credit: Catherine Sauvin" class="wp-image-19601"/><figcaption class="wp-element-caption"><em>Black-and-white ruffed lemur (</em>Varecia v. variegata<em>), Mantadia National Park. Credit: Catherine Sauvin</em></figcaption></figure>



<h2 class="wp-block-heading"><strong>Adapting our approach for other countries and regions</strong></h2>



<p>This method can be tested and adapted for use in other areas. National or local data sets of priority locations — such as natural forest maps, forest concessions, biodiversity corridors or community managed zones — can be overlaid with tree cover loss data to enable more accurate monitoring of deforestation across administrative and ecological zones. Tools such as the <a href="https://www.wri.org/initiatives/forest-atlases" target="_blank" rel="noreferrer noopener">Forest Atlases</a> — online platforms that help countries better manage their forest resources by combining government data with the latest forest monitoring technology — can also support these efforts. In addition, the contextual data sets such as <a href="http://gfw.global/3xmtCAV">intact forest maps</a>, and <a href="https://www.globalforestwatch.org/map/?map=eyJkYXRhc2V0cyI6W3siZGF0YXNldCI6Im5hdHVyYWwtZm9yZXN0cyIsIm9wYWNpdHkiOjEsInZpc2liaWxpdHkiOnRydWUsImxheWVycyI6WyJuYXR1cmFsLWZvcmVzdHMtMjAyMCJdfSx7ImRhdGFzZXQiOiJwb2xpdGljYWwtYm91bmRhcmllcyIsImxheWVycyI6WyJkaXNwdXRlZC1wb2xpdGljYWwtYm91bmRhcmllcyIsInBvbGl0aWNhbC1ib3VuZGFyaWVzIl0sIm9wYWNpdHkiOjEsInZpc2liaWxpdHkiOnRydWV9XX0%3D&amp;mapMenu=eyJtZW51U2VjdGlvbiI6ImRhdGFzZXRzIiwiZGF0YXNldENhdGVnb3J5IjoibGFuZENvdmVyIn0%3D">natural forest maps on GFW</a> can also be explored, and can reduce the effort required to process data, while other baselines such as tree height, biomass or strand structure can help identify areas likely to contain <a href="https://www.wri.org/insights/european-tall-forest-decline" target="_blank" rel="noreferrer noopener">older stands with higher carbon stocks</a>.</p>



<p>There are some limitations to this approach. The accuracy of annual deforestation estimates is in part determined by accuracy of the original forest map and the TCD thresholds assigned to each forested pixel. Additionally, this pixel-level approach requires significant computational resources, which can present challenges for large countries. Despite these constraints, the methodology remains robust.</p>



<p>While this work is specific to Madagascar, the same approach can be applied elsewhere. By starting with a nationally validated forest baseline, overlaying pixel-level TCD data and then applying annual tree cover loss, countries can adapt global data sets to their own ecological and administrative realities. This turns global monitoring tools into practical systems for national reporting, planning and conservation — ensuring that data is not only globally consistent, but also locally meaningful.</p>



<p>As satellite imagery and land cover data sets continue to improve, and as national definitions of forest types are refined, the precision and policy relevance of this approach will grow, offering countries a scalable, transparent way to monitor deforestation across ecological and administrative units.</p>



<h2 class="wp-block-heading"><strong>What’s next for deforestation analysis in Madagascar?</strong></h2>



<p>In the future, we plan to strengthen this approach in Madagascar by refining the natural forest map and expanding to include other relevant land cover types. Our current baseline for both the forest cover map and TCDs is the year 2000. While this early baseline offers valuable historical context, differences with more recent satellite data mean that long-term comparisons must be made with caution. For governments and practitioners, developing a consistent, high-quality data set covering the last 10 years and beyond may offer the most reliable basis for planning and evaluation.</p>



<p>As countries refine how they monitor land cover, Madagascar’s experience shows how global tools can be adapted to national ecological realities. This approach combines global satellite data with local knowledge to enable credible, independent monitoring of natural forests across all forest types and at relevant decision-making scales. Such monitoring is essential not only for conserving biodiversity, but also for sustaining the ecosystem services it underpins — services that support livelihoods, well-being and climate resilience for all who live on the island.</p>



<style type="text/css"></style>

Du global au local : un suivi forestier sur mesure pour Madagascar grâce aux données de Global Forest Watch

In 2024, WRI Madagascar developed an approach to bridge the gap between global tree cover loss data and deforestation within Madagascar’s natural forests.

Tailoring Forest Monitoring in Madagascar with GFW Data

https://secure.gravatar.com/avatar/be19f67e91ba81d93d32ae47706dcbb8?s=96&d=mm&r=g

Paige Johnson

commodities

commodities | Global Forest Watch Blog

fires

fires | Global Forest Watch Blog

Michelle Sims

Radost Stanimirova

Maxim Neumann

Anton Raichuk

Drew Purves 

New Data Shows What’s Driving Forest Loss Around the World

New data provides a more detailed picture than ever before on the local, regional and global causes of tree cover loss.

Users In Action

Hear stories from the forest defenders working in the field.

Users In Action | Global Forest Watch Blog

Indonesia

Indonesia | Global Forest Watch Blog

logging

logging | Global Forest Watch Blog

Mirzha Hanifah

Benita Nathania

Deden Pramudyana

Harnessing Technology, Raising a New Generation of Forest Monitors

WRI Indonesia and the IFM Fund are laying the groundwork for a new generation of forest monitors to contribute to environmental protection in Indonesia.

Harnessing Technology, Raising a New Generation of Forest Monitors | Users In Action | Global Forest Watch Blog

mapping

mapping | Global Forest Watch Blog

policy

policy | Global Forest Watch Blog

Viviana Zalles

Fred Stolle

Matt Hansen

How Rethinking ‘What Is a Forest’ Can Result in More Effective Conservation

How we define "what is a forest?" can have major implications for how forests — and more importantly, changes to forests — are measured.

How Rethinking ‘What Is a Forest’ Can Result in More Effective Conservation | Forest Insights | Global Forest Watch Blog

indigenous peoples

indigenous peoples | Global Forest Watch Blog

Katie Reytar

Ke Wang

Melissa Barbanell

Mining Is Increasingly Pushing into Critical Rainforests and Protected Areas